1,428 research outputs found
Analytic calculation of energy transfer and heat flux in a one-dimensional system
In the context of the problem of heat conduction in one-dimensional systems,
we present an analytical calculation of the instantaneous energy transfer
across a tagged particle in a one-dimensional gas of equal-mass, hard-point
particles. From this, we obtain a formula for the steady-state energy flux, and
identify and separate the mechanical work and heat conduction contributions to
it. The nature of the Fourier law for the model, and the nonlinear dependence
of the rate of mechanical work on the stationary drift velocity of the tagged
particle, are analyzed and elucidated.Comment: 17 pages including title pag
Critical Behaviour of Non-Equilibrium Phase Transitions to Magnetically Ordered States
We describe non-equilibrium phase transitions in arrays of dynamical systems
with cubic nonlinearity driven by multiplicative Gaussian white noise.
Depending on the sign of the spatial coupling we observe transitions to
ferromagnetic or antiferromagnetic ordered states. We discuss the phase
diagram, the order of the transitions, and the critical behaviour. For global
coupling we show analytically that the critical exponent of the magnetization
exhibits a transition from the value 1/2 to a non-universal behaviour depending
on the ratio of noise strength to the magnitude of the spatial coupling.Comment: 4 pages, 5 figure
Noise-Driven Mechanism for Pattern Formation
We extend the mechanism for noise-induced phase transitions proposed by
Ibanes et al. [Phys. Rev. Lett. 87, 020601-1 (2001)] to pattern formation
phenomena. In contrast with known mechanisms for pure noise-induced pattern
formation, this mechanism is not driven by a short-time instability amplified
by collective effects. The phenomenon is analyzed by means of a modulated mean
field approximation and numerical simulations
Knelpunten in aquacultuur: enkele risicovolle aspecten van de vroege levensstadia van de vis = Bottlenecks in aquaculture: some risky aspects of early life stages of fish
Aquaculture is a fast growing sector. However, during larviculture and fish husbandry, many bottlenecks still occur. Many problems concern nutritional factors and can be avoided by a clear understanding of the development of the gastrointestinal system of the various fish species. Parameters, such as enterocyte height, the presence of enterocytic supranuclear vacuoles and ‘the point of no return’, can be used to monitor and prevent food deprivation. This information can also be used to compose a feeding regime with rotifers, Artemia and copepods
On the impact of video stalling and video quality in the case of camera switching during adaptive streaming of sports content
The widespread usage of second screens, in combination with mobile video streaming technologies like HTTP Adaptive Streaming (HAS), enable new means for taking end-users' Quality of Experience (QoE) to the next level. For sports events, these technological evolutions can, for example, enhance the overall engagement of remote fans or give them more control over the content. In this paper, we consider the case of adaptively streaming multi-camera sports content to tablet devices, enabling the end-user to dynamically switch cameras. Our goal is to subjectively evaluate the trade-off between video stalling duration (as a result of requesting another camera feed) and initial video quality of the new feed. Our results show that short video stallings do not significantly influence overall quality ratings, that quality perception is highly influenced by the video quality at the moment of camera switching and that large quality fluctuations should be avoided
Determination of Dark Energy by the Einstein Telescope: Comparing with CMB, BAO and SNIa Observations
A design study is currently in progress for a third generation
gravitational-wave (GW) detector called Einstein Telescope (ET). An important
kind of source for ET will be the inspiral and merger of binary neutron stars
(BNS) up to . If BNS mergers are the progenitors of short-hard
-ray bursts, then some fraction of them will be seen both
electromagnetically and through GW, so that the luminosity distance and the
redshift of the source can be determined separately. An important property of
these `standard sirens' is that they are \emph{self-calibrating}: the
luminosity distance can be inferred directly from the GW signal, with no need
for a cosmic distance ladder. Thus, standard sirens will provide a powerful
independent check of the CDM model. In previous work, estimates were
made of how well ET would be able to measure a subset of the cosmological
parameters (such as the dark energy parameter ) it will have access to,
assuming that the others had been determined to great accuracy by alternative
means. Here we perform a more careful analysis by explicitly using the
potential Planck CMB data as prior information for these other parameters. We
find that ET will be able to constrain and with accuracies and , respectively. These results are compared
with projected accuracies for the JDEM Baryon Acoustic Oscillations project and
the SNAP Type Ia supernovae observations.Comment: 28 pages, 5 figures, 5 tables; Published Versio
First order phase transition in a nonequilibrium growth process
We introduce a simple continuous model for nonequilibrium surface growth. The
dynamics of the system is defined by the KPZ equation with a Morse-like
potential representing a short range interaction between the surface and the
substrate. The mean field solution displays a non trivial phase diagram with a
first order transition between a growing and a bound surface, associated with a
region of coexisting phases, and a tricritical point where the transition
becomes second order. Numerical simulations in 3 dimensions show quantitative
agreement with mean field results, and the features of the phase space are
preserved even in 2 dimensions.Comment: 7 figures, revtex, submitted to Phys. Rev.
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